BACKGROUND The high incidence and mortality of gastric cancer(GC)pose a significant threat to human life and health,and it has become an important public health challenge in China.Body weight loss is a common complica...BACKGROUND The high incidence and mortality of gastric cancer(GC)pose a significant threat to human life and health,and it has become an important public health challenge in China.Body weight loss is a common complication after surgical treatment in patients with GC and is associated with poor prognosis and GC recurrence.However,current attention to postoperative weight change in GC patients remains insufficient,and the descriptions of postoperative weight change and its influencing factors are also different.AIM To investigate body weight changes in patients with GC within 6 mo after gastrectomy and identify factors that influence dynamic body weight changes.METHODS We conducted a prospective longitudinal study of 121 patients with GC and collected data before(T0)and 1(T1),3(T2),and 6(T3)mo after gastrectomy using a general data questionnaire,psychological distress thermometer,and body weight measurements.The general estimation equation(GEE)was used to analyze the dynamic trends of body weight changes and factors that influence body weight changes in patients with GC within 6 mo of gastrectomy.RESULTS The median weight loss at T1,T2,and T3 was 7.29%(2.84%,9.40%),11.11%(7.64%,14.91%),and 14.75%(8.80%,19.84%),respectively.The GEE results showed that preoperative body mass index(BMI),significant psychological distress,religious beliefs,and sex were risk factors for weight loss in patients with GC within 6 mo after gastrectomy(P<0.05).Compared with preoperative low-weight patients,preoperative obese patients were more likely to have weight loss(β=14.685,P<0.001).Furthermore,patients with significant psychological distress were more likely to lose weight than those without(β=2.490,P<0.001),and religious patients were less likely to lose weight 6 mo after gastrectomy than those without religious beliefs(β=-6.844,P=0.001).Compared to female patients,male patients were more likely to experience weight loss 6 mo after gastrectomy(β=4.262,P=0.038).CONCLUSION Male patients with GC with high preoperative BMI,significant psychological distress,and no religious beliefs are more likely to lose weight after gastrectomy.展开更多
Standing-wave supermode microresonators that are created through the strong coupling between counter-propagating modes have emerged as versatile platforms for sensing and nonlinear optics.For example,these microresona...Standing-wave supermode microresonators that are created through the strong coupling between counter-propagating modes have emerged as versatile platforms for sensing and nonlinear optics.For example,these microresonators have shown potential in nanoparticle sizing and counting,as well as enhancing the single-photon optomechanical coupling rate of stimulated Brillouin scattering.However,it has been observed that the relation between the mode linewidth and on-resonance transmission of the split supermodes differs obviously from that of the non-split modes.This behavior is typically quantified by the coupling ideality(I),which remains inadequately explored for the standing-wave supermodes.In this study,we theoretically and experimentally investigate the coupling ideality of standing-wave supermodes in a commonly employed configuration involving a Si O2microresonator side-coupled to a tapered fiber.Our findings demonstrate that,even with a single-mode tapered fiber,the coupling ideality of the standing-wave supermodes is limited to 0.5,due to the strong backscattering-induced energy loss into the counter-propagating direction,resulting in an additional equivalent parasitic loss.While achieving a coupling ideality of 0.5 presents challenges for reaching over-coupled regimes,it offers a convenient approach for adjusting the total linewidth of the modes while maintaining critically-coupled conditions.展开更多
Ultrasound sensors play an important role in biomedical imaging,industrial nondestructive inspection,etc.Traditional ultrasound sensors that use piezoelectric transducers face limitations in sensitivity and spatial re...Ultrasound sensors play an important role in biomedical imaging,industrial nondestructive inspection,etc.Traditional ultrasound sensors that use piezoelectric transducers face limitations in sensitivity and spatial resolution when miniaturized,with typical sizes at the millimeter to centimeter scale.To overcome these challenges,optical ultrasound sensors have emerged as a promising alternative,offering both high sensitivity and spatial resolution.In particular,ultrasound sensors utilizing high-quality factor(Q)optical microcavities have achieved unprecedented performance in terms of sensitivity and bandwidth,while also enabling mass production on silicon chips.In this review,we focus on recent advances in ultrasound sensing applications using three types of optical microcavities:Fabry-Perot cavities,π-phase-shifted Bragg gratings,and whispering gallery mode microcavities.We provide an overview of the ultrasound sensing mechanisms employed by these microcavities and discuss the key parameters for optimizing ultrasound sensors.Furthermore,we survey recent advances in ultrasound sensing using these microcavity-based approaches,highlighting their applications in diverse detection scenarios,such as photoacoustic imaging,ranging,and particle detection.The goal of this review is to provide a comprehensive understanding of the latest advances in ultrasound sensing with optical microcavities and their potential for future development in high-performance ultrasound imaging and sensing technologies.展开更多
In single microdisks,embedded active emitters intrinsically affect the cavity modes of the microdisks,resulting in trivial symmetric backscattering and low controllability.Here we demonstrate macroscopic control of th...In single microdisks,embedded active emitters intrinsically affect the cavity modes of the microdisks,resulting in trivial symmetric backscattering and low controllability.Here we demonstrate macroscopic control of the backscattering direction by optimizing the cavity size.The signature of the positive and negative backscattering directions in each single microdisk is confirmed with two strongly coupled microdisks.Furthermore,diabolical points are achieved at the resonance of the two microdisks,which agrees well with theoretical calculations considering the backscattering directions.Diabolical points in active optical structures pave the way for an implementation of quantum information processing with geometric phase in quantum photonic networks.展开更多
Whispering gallery mode(WGM)microcavities have been widely used for high-sensitivity ultrasound detection,owing to their optical and mechanical dual-resonance enhanced sensitivity.The ultrasound sensitivity of the cav...Whispering gallery mode(WGM)microcavities have been widely used for high-sensitivity ultrasound detection,owing to their optical and mechanical dual-resonance enhanced sensitivity.The ultrasound sensitivity of the cavity optomechanical system is fundamentally limited by thermal noise.In this work,we theoretically and experimentally investigate the thermal-noise-limited sensitivity of a WGM microdisk ultrasound sensor and optimize the sensitivity by varying the radius and a thickness of the microdisk,as well as using a trench structure around the disk.Utilizing a microdisk with a radius of 300μm and thickness of 2μm,we achieve a peak sensitivity of 1.18μPa Hz^(-1/2)at 82.6 k Hz.To the best of our knowledge,this represents the record sensitivity among cavity optomechanical ultrasound sensors.Such high sensitivity has the potential to improve the detection range of air-coupled ultrasound sensing technology.展开更多
Tunable whispering-gallery-mode(WGM)microcavities are promising devices for reconfigurable photonic applications such as widely tunable integrated lasers and reconfigurable optical filters for optical communication an...Tunable whispering-gallery-mode(WGM)microcavities are promising devices for reconfigurable photonic applications such as widely tunable integrated lasers and reconfigurable optical filters for optical communication and information processing.Scaling up these devices demands the ability to tune the optical resonances in an integrated manner over a full free spectral range(FSR).Here we propose a high-speed full FSR magnetic tuning scheme of an integrated silicon nitride(Si_(3)N_(4))double-disk microcavity.By coating a magnetostrictive film on the spokes and the central pad of the Si_(3)N_(4) cavity,magnetic tuning can be realized using a microcoil integrated on the same chip.An FSR tuning can be achieved by combining magnetostrictive strain with strong optomechanical interactions provided by the double-disk microcavity.We calculate the required magnetic flux density to tune an FSR(B_(FSR))as a function of several key geometric parameters,including the air gap,radius,width of the spokes and ring of the double-disk cavities,as well as the thickness of the magnetostrictive film.The proposed structure enables a full FSR tuning with a required magnetic flux density of milli-Tesla(mT)level.We also study the dynamic response of the integrated device with an alternating current(AC)magnetic field driving,and find that the tuning speed can reach hundreds of kHz in the air.展开更多
Although an accurate evaluation of the distribution of ultrafine particulate matter in air is of utmost significance to public health,the usually used PM2.5 index fails to provide size distribution information.Here we...Although an accurate evaluation of the distribution of ultrafine particulate matter in air is of utmost significance to public health,the usually used PM2.5 index fails to provide size distribution information.Here we demonstrate a low-profile and cavity-free size spectrometer for probing fine and ultrafine particulate matter by using the enhanced particle-perturbed scattering in strong optical evanescent fields of a nanofiber array.The unprecedented size resolution reaches 10 nm for detecting single 100-nm-diameter nanoparticles by employing uniform nanofibers and controlling the polarizations of the probe light.This size spectrometry was tested and used to retrieve the size distribution of particulate matter in the air of Beijing,yielding mass concentrations of nanoparticles,as a secondary exercise,consistent with the officially released data.This nanofiber-array probe shows potential for the full monitoring of air pollution and for studying early-stage haze evolution and can be further extended to explore nanoparticle interactions.展开更多
Magnetostrictive optomechanical cavities provide a new optical readout approach to room-temperature magnetometry.Here we report ultrasensitive and ultrahigh bandwidth cavity optomechanical magnetometers constructed by...Magnetostrictive optomechanical cavities provide a new optical readout approach to room-temperature magnetometry.Here we report ultrasensitive and ultrahigh bandwidth cavity optomechanical magnetometers constructed by embedding a grain of the magnetostrictive material Terfenol-D within a high quality(Q)optical microcavity on a silicon chip.By engineering their physical structure,we achieve a peak sensitivity of26 p T∕Hz1/2 p comparable to the best cryogenic microscale magnetometers,along with a 3 d B bandwidth as high as 11.3 MHz.Two classes of magnetic response are observed,which we postulate arise from the crystallinity of the Terfenol-D.This allows single crystalline and polycrystalline grains to be distinguished at the level of a single particle.Our results may enable applications such as lab-on-chip nuclear magnetic spectroscopy and magnetic navigation.展开更多
Many different types of toxins are produced by the fungus, Alternaria alternata (Fr.) Keissler. Little is known, however, regarding the influence of these toxins on insects. In this study, we investigated the toxin-...Many different types of toxins are produced by the fungus, Alternaria alternata (Fr.) Keissler. Little is known, however, regarding the influence of these toxins on insects. In this study, we investigated the toxin-induced inhibitory effects of the toxin produced by A. alternata on the rose aphid, Macrosiphum rosivorum, when the toxin was applied to leaves of the rose, Rosa chinensis. The results demonstrated that the purified crude toxin was non-harmful to rose plants and rose aphids, but had an intensive inhibitory effect on the multiplication of aphids. The inhibitory index against rose aphids reached 87.99% when rose plants were sprayed with the toxin solution at a low concentration. Further results from bioassays with aphids and high performance liquid chromatography (HPLC) analyses demon- strated that tenuazonic acid (TEA) was one of the most important resistance-related active components in the crude toxin. The content of TeA was 0.1199% in the crude toxin under the HPLC method. Similar to the crude toxin, the inhibitory index of pure TeA reached 83.60% 15 d after the rose plants were sprayed with pure TeA solution at the lower concentration of 0.060 IJg/ml, while the contents of residual TeA on the surface and in the inner portion of the rose plants were only 0.04 and 0.00 ng/g fresh weight of TeA-treated rose twigs, respectively, 7 d after the treatment. Our results show that TeA, an active component in the A. alternata toxin, can induce the indirect plant-mediated re- sponses in rose plants to intensively enhance the plant's resistances against rose aphids, and the results are very helpful to understand the plant-mediated interaction between fungi and insects on their shared host plants.展开更多
Crystal-phase low-dimensional structures offer great potential for the implementation of photonic devices of interest for quantum information processing.In this context,unveiling the fundamental parameters of the crys...Crystal-phase low-dimensional structures offer great potential for the implementation of photonic devices of interest for quantum information processing.In this context,unveiling the fundamental parameters of the crystal phase structure is of much relevance for several applications.Here,we report on the anisotropy of the g-factor tensor and diamagnetic coefficient in wurtzite/zincblende(WZ/ZB)crystal-phase quantum dots(QDs)realized in single InP nanowires.The WZ and ZB alternating axial sections in the NWs are identified by high-angle annular dark-field scanning transmission electron microscopy.The electron(hole)g-factor tensor and the exciton diamagnetic coefficients in WZ/ZB crystal-phase QDs are determined through micro-photoluminescence measurements at low temperature(4.2 K)with different magnetic field configurations,and rationalized by invoking the spin-correlated orbital current model.Our work provides key parameters for band gap engineering and spin states control in crystal-phase low-dimensional structures in nanowires.展开更多
文摘BACKGROUND The high incidence and mortality of gastric cancer(GC)pose a significant threat to human life and health,and it has become an important public health challenge in China.Body weight loss is a common complication after surgical treatment in patients with GC and is associated with poor prognosis and GC recurrence.However,current attention to postoperative weight change in GC patients remains insufficient,and the descriptions of postoperative weight change and its influencing factors are also different.AIM To investigate body weight changes in patients with GC within 6 mo after gastrectomy and identify factors that influence dynamic body weight changes.METHODS We conducted a prospective longitudinal study of 121 patients with GC and collected data before(T0)and 1(T1),3(T2),and 6(T3)mo after gastrectomy using a general data questionnaire,psychological distress thermometer,and body weight measurements.The general estimation equation(GEE)was used to analyze the dynamic trends of body weight changes and factors that influence body weight changes in patients with GC within 6 mo of gastrectomy.RESULTS The median weight loss at T1,T2,and T3 was 7.29%(2.84%,9.40%),11.11%(7.64%,14.91%),and 14.75%(8.80%,19.84%),respectively.The GEE results showed that preoperative body mass index(BMI),significant psychological distress,religious beliefs,and sex were risk factors for weight loss in patients with GC within 6 mo after gastrectomy(P<0.05).Compared with preoperative low-weight patients,preoperative obese patients were more likely to have weight loss(β=14.685,P<0.001).Furthermore,patients with significant psychological distress were more likely to lose weight than those without(β=2.490,P<0.001),and religious patients were less likely to lose weight 6 mo after gastrectomy than those without religious beliefs(β=-6.844,P=0.001).Compared to female patients,male patients were more likely to experience weight loss 6 mo after gastrectomy(β=4.262,P=0.038).CONCLUSION Male patients with GC with high preoperative BMI,significant psychological distress,and no religious beliefs are more likely to lose weight after gastrectomy.
基金National Key Research and Development Program of China(2021YFA1400700)National Natural Science Foundation of China(62222515,12174438,11934019,91950118)+1 种基金Basic Frontier Science Research Program of Chinese Academy of Sciences(ZDBS-LYJSC003)CAS Project for Young Scientists in Basic Research(YSBR-100)。
文摘Standing-wave supermode microresonators that are created through the strong coupling between counter-propagating modes have emerged as versatile platforms for sensing and nonlinear optics.For example,these microresonators have shown potential in nanoparticle sizing and counting,as well as enhancing the single-photon optomechanical coupling rate of stimulated Brillouin scattering.However,it has been observed that the relation between the mode linewidth and on-resonance transmission of the split supermodes differs obviously from that of the non-split modes.This behavior is typically quantified by the coupling ideality(I),which remains inadequately explored for the standing-wave supermodes.In this study,we theoretically and experimentally investigate the coupling ideality of standing-wave supermodes in a commonly employed configuration involving a Si O2microresonator side-coupled to a tapered fiber.Our findings demonstrate that,even with a single-mode tapered fiber,the coupling ideality of the standing-wave supermodes is limited to 0.5,due to the strong backscattering-induced energy loss into the counter-propagating direction,resulting in an additional equivalent parasitic loss.While achieving a coupling ideality of 0.5 presents challenges for reaching over-coupled regimes,it offers a convenient approach for adjusting the total linewidth of the modes while maintaining critically-coupled conditions.
基金supported by The National Key Research and Development Program of China(2021YFA1400700)the National Natural Science Foundation of China(NSFC)(62222515,12174438,91950118,11934019)+2 种基金the basic frontier science research program of Chinese Academy of Sciences(ZDBS-LY-JSC003)CAS Project for Young Scientists in Basic Research(YSBR-100)supported by the Micro/nano Fabrication Laboratory of Synergetic Extreme Condition User Facility(SECUF).
文摘Ultrasound sensors play an important role in biomedical imaging,industrial nondestructive inspection,etc.Traditional ultrasound sensors that use piezoelectric transducers face limitations in sensitivity and spatial resolution when miniaturized,with typical sizes at the millimeter to centimeter scale.To overcome these challenges,optical ultrasound sensors have emerged as a promising alternative,offering both high sensitivity and spatial resolution.In particular,ultrasound sensors utilizing high-quality factor(Q)optical microcavities have achieved unprecedented performance in terms of sensitivity and bandwidth,while also enabling mass production on silicon chips.In this review,we focus on recent advances in ultrasound sensing applications using three types of optical microcavities:Fabry-Perot cavities,π-phase-shifted Bragg gratings,and whispering gallery mode microcavities.We provide an overview of the ultrasound sensing mechanisms employed by these microcavities and discuss the key parameters for optimizing ultrasound sensors.Furthermore,we survey recent advances in ultrasound sensing using these microcavity-based approaches,highlighting their applications in diverse detection scenarios,such as photoacoustic imaging,ranging,and particle detection.The goal of this review is to provide a comprehensive understanding of the latest advances in ultrasound sensing with optical microcavities and their potential for future development in high-performance ultrasound imaging and sensing technologies.
基金supported by the National Natural Science Foundation of China under Grant No.11934019,No.11721404,No.51761145104,No.61675228,and No.11874419the Ministry of Science and Technology of China under Grant No.2016YFA0200400+3 种基金the Strategic Priority Research Program under Grant No.XDB07030200,No.XDB28000000,and No.XDB07020200the Instrument Developing Project under Grant No.YJKYYQ20180036the Interdisciplinary Innovation Team of the Chinese Academy of Sciencesthe Key R&D Program of Guangdong Province under Grant No.2018B030329001.
文摘In single microdisks,embedded active emitters intrinsically affect the cavity modes of the microdisks,resulting in trivial symmetric backscattering and low controllability.Here we demonstrate macroscopic control of the backscattering direction by optimizing the cavity size.The signature of the positive and negative backscattering directions in each single microdisk is confirmed with two strongly coupled microdisks.Furthermore,diabolical points are achieved at the resonance of the two microdisks,which agrees well with theoretical calculations considering the backscattering directions.Diabolical points in active optical structures pave the way for an implementation of quantum information processing with geometric phase in quantum photonic networks.
基金National Key Research and Development Program of China (2021YFA1400700)National Natural Science Foundation of China (11934019,12174438,62222515,91950118)Basic Frontier Science Research Program of Chinese Academy of Sciences (ZDBS-LY-JSC003)。
文摘Whispering gallery mode(WGM)microcavities have been widely used for high-sensitivity ultrasound detection,owing to their optical and mechanical dual-resonance enhanced sensitivity.The ultrasound sensitivity of the cavity optomechanical system is fundamentally limited by thermal noise.In this work,we theoretically and experimentally investigate the thermal-noise-limited sensitivity of a WGM microdisk ultrasound sensor and optimize the sensitivity by varying the radius and a thickness of the microdisk,as well as using a trench structure around the disk.Utilizing a microdisk with a radius of 300μm and thickness of 2μm,we achieve a peak sensitivity of 1.18μPa Hz^(-1/2)at 82.6 k Hz.To the best of our knowledge,this represents the record sensitivity among cavity optomechanical ultrasound sensors.Such high sensitivity has the potential to improve the detection range of air-coupled ultrasound sensing technology.
基金funding support from the National Natural Science Foundation of China(91950118,62222515,12174438,11934019)the National Key Research and Development Program of China(2021YFA1400700)the basic frontier science research pro-gram of Chinese Academy of Sciences(ZDBS-LY-JSC003).
文摘Tunable whispering-gallery-mode(WGM)microcavities are promising devices for reconfigurable photonic applications such as widely tunable integrated lasers and reconfigurable optical filters for optical communication and information processing.Scaling up these devices demands the ability to tune the optical resonances in an integrated manner over a full free spectral range(FSR).Here we propose a high-speed full FSR magnetic tuning scheme of an integrated silicon nitride(Si_(3)N_(4))double-disk microcavity.By coating a magnetostrictive film on the spokes and the central pad of the Si_(3)N_(4) cavity,magnetic tuning can be realized using a microcoil integrated on the same chip.An FSR tuning can be achieved by combining magnetostrictive strain with strong optomechanical interactions provided by the double-disk microcavity.We calculate the required magnetic flux density to tune an FSR(B_(FSR))as a function of several key geometric parameters,including the air gap,radius,width of the spokes and ring of the double-disk cavities,as well as the thickness of the magnetostrictive film.The proposed structure enables a full FSR tuning with a required magnetic flux density of milli-Tesla(mT)level.We also study the dynamic response of the integrated device with an alternating current(AC)magnetic field driving,and find that the tuning speed can reach hundreds of kHz in the air.
基金supported by the NSFC(Grant Nos.61435001,61611540346,11474011 and 11654003)the National Key R&D Program of China(Grant No.2016YFA0301302)supported by the China Postdoctoral Science Foundation(Grant No.2015M580909).
文摘Although an accurate evaluation of the distribution of ultrafine particulate matter in air is of utmost significance to public health,the usually used PM2.5 index fails to provide size distribution information.Here we demonstrate a low-profile and cavity-free size spectrometer for probing fine and ultrafine particulate matter by using the enhanced particle-perturbed scattering in strong optical evanescent fields of a nanofiber array.The unprecedented size resolution reaches 10 nm for detecting single 100-nm-diameter nanoparticles by employing uniform nanofibers and controlling the polarizations of the probe light.This size spectrometry was tested and used to retrieve the size distribution of particulate matter in the air of Beijing,yielding mass concentrations of nanoparticles,as a secondary exercise,consistent with the officially released data.This nanofiber-array probe shows potential for the full monitoring of air pollution and for studying early-stage haze evolution and can be further extended to explore nanoparticle interactions.
基金Defense Advanced Research Projects Agency(Qu ASAR Program)Australian Research Council(DP140100734,FT140100650)+1 种基金Defence Science and Technology Group(CERA49,CERA50)University of Queensland(2014001447)。
文摘Magnetostrictive optomechanical cavities provide a new optical readout approach to room-temperature magnetometry.Here we report ultrasensitive and ultrahigh bandwidth cavity optomechanical magnetometers constructed by embedding a grain of the magnetostrictive material Terfenol-D within a high quality(Q)optical microcavity on a silicon chip.By engineering their physical structure,we achieve a peak sensitivity of26 p T∕Hz1/2 p comparable to the best cryogenic microscale magnetometers,along with a 3 d B bandwidth as high as 11.3 MHz.Two classes of magnetic response are observed,which we postulate arise from the crystallinity of the Terfenol-D.This allows single crystalline and polycrystalline grains to be distinguished at the level of a single particle.Our results may enable applications such as lab-on-chip nuclear magnetic spectroscopy and magnetic navigation.
基金supported by the National Natural Science Foundation of China(No.31160354)the Foundation of the Education Department of Yunnan Province in China(No.2013Y120)
文摘Many different types of toxins are produced by the fungus, Alternaria alternata (Fr.) Keissler. Little is known, however, regarding the influence of these toxins on insects. In this study, we investigated the toxin-induced inhibitory effects of the toxin produced by A. alternata on the rose aphid, Macrosiphum rosivorum, when the toxin was applied to leaves of the rose, Rosa chinensis. The results demonstrated that the purified crude toxin was non-harmful to rose plants and rose aphids, but had an intensive inhibitory effect on the multiplication of aphids. The inhibitory index against rose aphids reached 87.99% when rose plants were sprayed with the toxin solution at a low concentration. Further results from bioassays with aphids and high performance liquid chromatography (HPLC) analyses demon- strated that tenuazonic acid (TEA) was one of the most important resistance-related active components in the crude toxin. The content of TeA was 0.1199% in the crude toxin under the HPLC method. Similar to the crude toxin, the inhibitory index of pure TeA reached 83.60% 15 d after the rose plants were sprayed with pure TeA solution at the lower concentration of 0.060 IJg/ml, while the contents of residual TeA on the surface and in the inner portion of the rose plants were only 0.04 and 0.00 ng/g fresh weight of TeA-treated rose twigs, respectively, 7 d after the treatment. Our results show that TeA, an active component in the A. alternata toxin, can induce the indirect plant-mediated re- sponses in rose plants to intensively enhance the plant's resistances against rose aphids, and the results are very helpful to understand the plant-mediated interaction between fungi and insects on their shared host plants.
基金This work was supported by the National Natural Science Foundation of China(Nos.11934019,61675228,11721404,51761145104,and 11874419)the Strategic Priority Research Program,the Instrument Developing Project and the Interdisciplinary Innovation Team of the Chinese Academy of Sciences(Nos.XDB28000000 and YJKYYQ20180036)+2 种基金the Key RD Program of Guangdong Province(No.2018B030329001)the Key Laboratory Fund(No.614280303051701)We acknowledge financial support from the SUPERTOP project,QUANTERA ERA-NET Cofund in Quantum Technologies.
文摘Crystal-phase low-dimensional structures offer great potential for the implementation of photonic devices of interest for quantum information processing.In this context,unveiling the fundamental parameters of the crystal phase structure is of much relevance for several applications.Here,we report on the anisotropy of the g-factor tensor and diamagnetic coefficient in wurtzite/zincblende(WZ/ZB)crystal-phase quantum dots(QDs)realized in single InP nanowires.The WZ and ZB alternating axial sections in the NWs are identified by high-angle annular dark-field scanning transmission electron microscopy.The electron(hole)g-factor tensor and the exciton diamagnetic coefficients in WZ/ZB crystal-phase QDs are determined through micro-photoluminescence measurements at low temperature(4.2 K)with different magnetic field configurations,and rationalized by invoking the spin-correlated orbital current model.Our work provides key parameters for band gap engineering and spin states control in crystal-phase low-dimensional structures in nanowires.